(1) Field of the Invention
The present invention relates generally to petroleum dispensing systems and, more particularly, to a dispenser data distribution system with controllable disconnectors for improving the conventional wiring connecting dispenser data circuits to the system's site controls and point of sale terminals.
(2) Description of the Prior Art
Service stations for delivering fuel to automobiles include a plurality of fuel dispensers that are typically stationed adjacent to a convenience store. Each fuel dispenser is made up of a housing, a regulator or pump to control the flow of fuel through the housing, a fuel flow meter in the housing, a display on the housing to display the amount of fuel pumped through the housing, and a fuel hose with nozzle having a manual dispenser control for delivering fuel into an automobile's fuel tank.
A dispenser data distribution system comprises low voltage communication circuitry that conducts data signals between the plurality of fuel dispensers and at least one point of sales terminal that is typically inside of the convenience store. While present day service stations do include emergency shutdown circuits for the line voltage that operates the dispenser pumps, the prior art does not allow for emergency disconnection of the low voltage data communication circuitry from fuel dispensers. The lack of emergency shutdown for these low voltage data communication circuits still presents a significant safety hazard in that it has been discovered that low voltage communication circuits can act as an ignition source for volatile gases associated with the delivery of petroleum based fuels such as gasoline.
Moreover, conventional dispenser data distribution systems that provide a dispenser servicing disconnect switch do not provide any way to disconnect all data circuits for a select dispenser with operation of the single switch. The present invention overcomes this problem by providing a disconnector circuit in which the operation of a single selected dispenser control switch can control multiple data circuits for the selected dispenser. While a system for a single dispenser could be constructed, a system with switches and controls for multiple dispensers contained in a single system would be the most desirable.
It can be appreciated that fueling data distribution systems have been in use for years. Typically, fueling data distribution systems are comprised of a dispenser data distribution box used to connect dispenser data wiring to a dispenser site controller.
The main problem with conventional fueling data distribution systems is that they do not provide a disconnector circuit for disconnecting all of the data circuits from power supply sources in response to the operation of the electrical emergency stop system at the site. Furthermore conventional systems do not provide a disconnector circuit for individually disconnecting all of the data circuits for a single dispenser from supply source in response to the operation of a service control switch.
Yet, another problem with conventional fueling data distribution systems is that they do not provide any emergency disconnect circuitry for de-energizing additional data circuits such as intercoms, networking, and video circuits. Still, another problem with conventional fueling data distribution systems is that they do not provide any way of providing individual connection for all data circuits per dispenser. Therefore, additional connections have to be made manually by the installer.
While conventional dispenser data distribution systems may be suitable for the particular purpose to which they address, they are not as suitable for improving on the conventional wiring connecting dispenser data circuits to the site controls. Conventional dispenser data distribution system wiring does not provide any way of controlling dispenser data circuits by an emergency stop system. Additionally, conventional dispenser data distribution system wiring that does provide a dispenser servicing disconnect switch does not provide a disconnect circuit to disconnect all data circuits for a select dispenser with operation of the single switch.
Thus, there remains a need for a new and improved dispenser data distribution system that improves on the conventional wiring that connects dispenser data circuits to the site controls. Moreover, there remains a need for a dispenser data distribution system that includes an emergency stop system for disconnecting supply power sources from the dispenser data circuitry. In other words, the dispenser's data circuits should be de-energized by a single switch emergency stop system.